Tens of thousands of people marched through Dublin yesterday in the one of the country's biggest ever anti-abortion demonstrations.

Participants in the Rally for Life marched from Parnell Square to Merrion Square, where they were addressed by speakers calling for the retention of the Eighth Amendment in the Constitution, which protects life in the womb.

Placard-waving marchers were 10 to 12 abreast at the front of the march as they arrived at Merrion Square while marchers near the rear of the crowd were still leaving O'Connell Street.The demonstration stretched for well over a kilometre through the city.

Organisers stated 100,000 people joined the rally. The Save the 8th Campaign said the sheer size of the demonstration made it clear to the Government the extent of opposition to its plan for "a UK-style abortion regime" in Ireland.

Mattie McGrath fears set up of abortion clinics. Photo: Tony Gavin

Speakers at the rally included doctors and people with disabilities.

A GP, Dr Judy Ceannt, told the crowd: "The basic law that governs our actions as doctors is first do no harm.

"We are not meant to intentionally kill or harm any patient, least of all the most helpless, the unborn baby. The government has no right to impose this on us."

A majority of Irish GPs in a recent survey said they would not prescribe the abortion pill.

Another doctor, Maire Neasta Nic Gearailt, said she would present an optician's voucher to Senator Catherine Noone, chair of the Oireachtas Committee which recommended Repeal of the Eighth, because the senator said she "could not find" any pro-Eighth Amendment doctors.

Ms Charlie Fien, a Down syndrome activist, spoke against the targeting of Down syndrome children in the womb for abortion. She said: "Saving the Eighth will save the lives of babies with Down syndrome. Ireland is one of the only countries in the world where babies with Down syndrome are safe inside their mother's wombs."

Save the 8th Campaign manager Niamh Ui Bhriain said "Our message will be focused on ensuring that the Irish people vote 'No' to this extreme abortion referendum.

"One of the heartbreaking facts we have seen emerging from Britain is that 90pc of babies with Down syndrome are aborted before birth. Charlie Fien's call to protect babies with a disability is hugely important."

Destiny Herndon-De La Rosa, who said she was a pro-life feminist, said abortion was "the ultimate exploitation of women, and is a symptom of women's oppression".

Businessman Declan Ganley said the coming weeks would be "a battle between the people and the powerful - with the political elites and the taxpayer-funded lobby groups on one side, and the ordinary people on the other".

"For three or four years there has been a relentless drumbeat for abortion from the media and people in cushy taxpayer-funded lobby groups," he added.

Mattie McGrath TD said abortion clinics would set up in Ireland seeking business despite assurances from the Government that clinics would not be established if the amendment was repealed.

A silent protest against the huge march was mounted by about a dozen people, mainly women, outside the GPO as the marchers went past. A 21-year-old Dublin woman, who claimed she was a member of 'Radical Queer Resist,' said: "I'm not happy with people marching against my human rights."